South Korean police estimate 50,000 people turned out in Seoul Saturday in the latest protest against the resumption of U.S. beef imports.

About 20,000 riot police were deployed throughout the capital. There were no clashes between protesters and police.

Large protests have been held in Seoul on a near-daily basis since the new government of President Lee Myung-bak agreed to resume U.S. beef imports in April. The protests were sparked by fears of mad cow disease, which triggered a ban on American beef imports in 2003.

The protests forced Seoul to renegotiate the deal to limit U.S. beef from cattle under 30 months old, which are considered less susceptible to mad cow disease.

The rallies have declined in number since an estimated 80,000 people gathered in Seoul on June 10, but some have turned violent in recent days.

The protests have evolved into an expression of outrage against Mr. Lee's policies.

U.S. beef went back on the South Korean market this week. Retailers say the initial sales of U.S. beef have been successful, despite major supermarkets' reluctance to sell it for fear of a public backlash.

Some information for this report was provided by AFP and Reuters.